Impact of BMI and obesity on oral health: an independent relationship
MedWire News: High body mass index (BMI) and obesity negatively impact on oral health, independent of dietary patterns and insulin resistance, French research shows.
It is known that poor oral health is linked to increasing BMI, however, the cause of this effect is not known.
In the present study, Jacques Amar (Toulouse University) and colleagues examined the link between BMI and markers of oral health before and after controlling for confounding factors such as dietary patterns and insulin resistance.
Subjects were taken from a single center participating in the MONA LISA survey, which was a multicenter, cross-sectional study of 4800 people, studying the prevalence of cardiovascular risk factors in the general in French population.
From a population of 1626, and following exclusions, nutritional data were available for 186 participants (aged 54 years on average), and these formed the group for this study.
The average body mass index was 26.1 kg/m2. Participants were divided into quartiles of BMI ranges: 18.7-22.9, 23.0-25.4, 25.5-28.2, and 28.3-43.2 kg/m2.
Dental examination was performed for each of the participants, consisting of assessment of teeth number, presence of periodontitis, plaque index (PI), clinical attachment loss (CAL), probing pocket depth (PD), and gingival index (GI).
Increasing BMI was significantly associated with an increased frequency of more than two missing teeth, ranging from 28% for the first quartile to 60% for the fourth quartile. Increasing BMI was also associated with increased frequency of severe periodontitis (20% to 49%), participants with more than two PI sites (9% to 38%) and subjects with PD greater than or equal to 4 mm (9% to 36%).
After adjustment for confounders (age, gender, education level, smoking habits, physical activity, total energy intake, and C-reactive protein levels) presenting with missing teeth (odds ratio [OR]=2.17), PD greater than or equal to 4 mm (OR=2.19) and PI greater than or equal to two (OR=2.38) were significantly associated with increasing BMI.
Following inclusion of whether the patient followed a high carbohydrate diet, significance was maintained for PD and PI, but not for number of missing teeth. This significance also held once insulin levels were included in the model.
Writing in Oral Diseases, Amar et al conclude that "our study identifies plaque index and pocket depth as the periodontal markers most strongly and independently related to obesity.
Future research will have to focus on the plausible mechanisms, including the investigation of the respective roles of inflammation, oral microflora, and insulin-resistance on weight gain."
By Iain Bartlett